The Adolescent Brain Cognitive Development (ABCD) Study is the largest study of brain development and child health in the United States. The ABCD Study is a nationwide consortium of study sites, including the University of Minnesota, that will track over 11,000 children aged 9-10 to understand their biological and behavioral development through adolescence into young adulthood. The ABCD Study uses cutting-edge technology to determine how childhood and adolescent experiences (like sports, videogames, social media, unhealthy sleep patterns, and substance use) interact with one another and with changing biology to affect brain development and social, behavioral, academic, health, and other outcomes.